Saturday, October 18, 2014

Meteor M2 Images using RTL SDR

I tried decoding new Russian weather satellite “Meteor-M №2″ broadcasting at frequencies of 137.1 and 137.9 in the LRPT format with an Image resolution of 12 times greater than the aging analog NOAA APT signals.

Setup uses RTL SDR with E4000 tuner chipset, home brew QFH Antenna and a homebrew preamp.
There is heavy interferences on 137 Mhz from an unknown source, in-spite of it I have managed to decode some of the images, as and when time permits.

Most of these images were decoded using GNUradio (Ubuntu flavour of Linux) installed on flash drive with persistent mode and booted through it, special thanks to Raydel Aberu Espinetm CM2ESP for it. See details (PDF file).

M2 is now fully operation, but transmits only on 2 Vis Ch + 1 IR Ch during day time.

My two page setup was published in GEO MAGAZINE'S QUARTERLY ISSUE, DEC 2014.

Another image PUBLISHED IN GEO MAGAZINE'S QUARTERLY ISSUE, JUNE 2015.

My RTL Setup.

Through multi way switch, I can connect RTL directly to antenna or through 137 MHz preamp or use HF up convertor. It has its own power supply reducing interference from pc or its supply. When using my Samsung tab this prevents taxing Tab's battery.

I added some additional rf filters not shown in above photo to reduce interference.﻿

GNUradio screen shots, running Raydel's (CM2ESP) script .

Image Processing done by LRPToffLineDecoder under W7.

New QPSK Plugin developed by Vasili and Alex.

Meteor Images from above setup.

White band in the images is due toglitch on the RAW HRPT to LRPT JPEG compressor system on the satellite.